Water pressure

[Graham]

Hi, My hot and cistern fed cold water pressure is really poor and showers fed from this barely work.

I had a poke around in the loft and noticed the cold tank sat on chipboard on the ceiling joists. So from a shower point of view I have about 18" head. Would it be a good idea to get a load of 6x2 and raise the tank, extending the copper. I have room to raise it 5ft nearly and there is a supporting wall nearby that I can tie into. Its a big tank and must weigh a ton.

If I remember my school physics, doing that will increase pressure but are there any other implications? For example, is the hot water cylinder still OK? Will it unveal a load of dry joints in my system? Thanks

[Set Square]

Raising the tank *will* increase the pressure - but not by enough to induce leaks in your hot tank and pipework. [Incidentally, dry joints are what you want! - they are only bad in electrical/electronic circuits.]

You may *still* not get an adequate flow from your shower, though. A better solution would be to install a shower pump in the hot and cold feeds to the shower - triggered by a flow switch so that, as soon as you get *some* flow due to gravity, the pump kicks in and gives you a half-way decent shower. [You could also use the pump to fill the bath a bit faster if you have common feeds to the bath and shower, and install the pump before the split].

Make sure that you have an adequately sized feed pipe from the cold tank down into the bottom of the hot cylinder. This should be at least 22mm - preferably 28mm.

[Christian McArdle]

It will certainly increase the pressure and flow rate. However, it probably will be insufficient to make it acceptable. You might wish to consider using a pump instead. Probably less work to install as well. Pumps start from around 99 quid.

Christian.

[Capitol]

I'd say do both, raise tank and fit pump, with 28mm piping. Unless the input side of the pump gets enough flow, there is a tendency to suck air into the system from the hot tank vent tube.

regards Capitol

[IMM]

terminology: cold water storage "tank" hot water storage "cylinder"

Installing Surrey flange on the cylinders draw-off, will prevent air being sucked in.

[Dave Plowman]

6 ft of head with careful pipework and preferably 22mm in diameter will give a pretty decent shower.

[Capitol]

Not always, you can get cavitation effects and that's with both an Essex and a Surrey flange! Regards Capitol